I stumbled across a video on Dave's site with one of his 87 300Ds doing a 0-80 run. I took this and edited it with a 0-60 run I did in my 350SDL:

https://www.youtube.com/watch?v=dJh-fR8jXLY

Both cars seem to be about the same speed! It's also interesting that the 2-3 shift happens at exactly the same time in both cars, despite the different gearing and redline of the 2 engines! Looks like it's right at 50 mph. The 3.5 builds boost quicker, and also seems to load the torque converter up more before boost builds. The 3.0 has of course and extra 1000 rpm to work with.

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.